Gold Nanoparticle Embedded Stimuli-Responsive Functional Glycopolymer: A Potential Material for Synergistic Chemo-Photodynamic Therapy of Cancer Cells.

Photodynamic therapy has emerged as a noninvasive treatment modality for several types of cancers. However, conventional hydrophobic photosensitizers (PS) suffer from low water solubility and poor tumor-targeting ability. Therefore, PS modified with glycopolymers can offer adequate water solubility, biocompatibility, and tumor-targeting ability due to the presence of multiple sugar units. In this study, a well-defined block copolymer poly(3-O-methacryloyl-d-glucopyranose)-b-poly(2-(4-formylbenzoyloxy)ethylmethacrylate) (PMAG-b-PFBEMA) containing pendant glucose and aldehyde units is synthesized via reversible addition-fragmentation chain transfer polymerization method. A water-soluble PS (toluidine blue O; TBO) and a potent anticancer drug, Doxorubicin (Dox) are introduced to the polymer backbone via acid-labile Schiff-base reaction (PMAG-b-PFBEMA_TBO_Dox). The PMAG-b-PFBEMA_TBO_Dox is then anchored on the surface of gold nanoparticles (AuNPs) via electrostatic interaction. This hybrid system exhibits excellent reactive oxygen species (ROS) generating ability under exposure of 630 nm light-emitting diode along with triggered release of Dox under the acidic pH of tumor cells. The in vitro cytotoxicity study on human breast cancer cell line, MDA MB 231, for this hybrid system shows promising results due to the synergistic effect of ROS and Dox released. Thus, this glycopolymer-based dual (chemo-photodynamic) therapy model can work as potential material for future therapeutics.